The present invention relates to a means for guiding rails longitudinally comprising rails that fit together and can be displaced in a sliding manner with respect to each other without play, having a lower rail and a sliding displaceable upper rail; the invention relates also to the use of the play-free longitudinal guiding means.
Means of longitudinally guiding two displaceable sliding rails that fit into each other are known for example for sliding movement of equipment or devices. Such longitudinal guiding means are of great importance as longitudinal adjustment devices in the seats of vehicles, for example in automotive vehicles. Guiding means for longitudinal adjustment devices in vehicle seats where the said device comprises rails that fit together, at least one of which exhibits a shaped section with an approximately U-shaped cross-sectional profile, are known e.g. from the German patent document DE 31 22 124. One of the rails is a stationary guide rail and the sliding rail is displaceable in the longitudinal direction via roller-type parts. Additionally, spheres running in longitudinal struts form at least two further longitudinal guiding means.
Known from European Patent EP 0 130 275 are longitudinal guiding means intended in particular for vehicle seats, where two mutually displaceable longitudinal sliding rails fit together, are connected to each other and are in contact with each other under tension via two rows of roller-type parts, in particular spheres.
In practice, two versions of longitudinal guiding means for sliding, mutually displaceable vehicle seats have proved successful. For mechanically displaceable vehicle seats, longitudinal guiding means with some play that permits easy gliding has proved itself. Rails that mate together without play and can be moved only with high expenditure of energy have come into use for the version powered by electromotor drive. The large amount of force required can easily be provided by the electrical drive, and the absence of play, means that undesirable noises are avoided when the vehicle is in use. Longitudinal guiding means with little room for play tend to create disturbing noises while the vehicle is running, and give the impression of inferior construction.